What makes a person prefer coffee over tea or alcohol? A new study shows that genetics may actually play a part in it.
Bitterness
Bitter taste evolved as a warning to protect the body from any harmful substances, in that tasting it would supposedly make people want to spit the bitter, potentially harmful substance out. However, coffee, tea, and alcohol are all widely consumed beverages worldwide, all of which have an inherently bitter taste.
In past studies, researchers have identified three genetic variants associated with bitter taste perception: rs2597979 for caffeine, rs1726866 for propylthiouracil (PROP), and rs10772420 for quinine. PROP is a synthetic taste related to compounds in cruciferous vegetables, while quinine is a bitter compound that is derived from the bark of the cinchona tree.
In a new study, researchers set out to investigate how genetics might be playing a part in people’s preference and consumption of coffee, tea, or alcohol.
Caffeine-Sensitive People
For the study, researchers used Mendelian randomization to analyze the causal relationship between bitter taste and beverage consumption in over 430,000 men and women in Britain. In it, the genetic variants were tested for its associations with self-reported coffee, tea, and alcohol consumption of the participants.
“You’d expect that people who are particularly sensitive to the bitter taste of caffeine would drink less coffee,” said senior author Marilyn Cornelis. Interestingly, however, they found that those who were more sensitive to the bitterness of caffeine actually consumed more coffee and lower amounts of tea.
According to Cornelis, it’s possible that the higher consumption might be a result of the positive stimulation they get from caffeine.
Quinine And PROP-Sensitive People
On the other hand, those who were more sensitive to the bitterness of quinine and PROP tended to avoid coffee and drink more tea, while those more sensitive to the bitterness of PROP tended to drink less alcohol, particularly red wine.
Simply put, the researchers surmise that it’s possible for people’s preferences for bitter beverages to be determined or informed by genetics. Furthermore, study lead Jue Sheng Ong also shares that the results also show that despite the many types and iterations of coffee, perhaps most of it still share similar profiles.
The study is published in Scientific Reports.